Most homes have a front outdoor light. The light serves the dual purpose of lighting the way for occupants and guests and also for discouraging unwanted guests such as prowlers or burglars.
In order for the front light to serve its purpose, typically someone has to be home at dusk to turn the light on. If not, an unlighted front walkway may pose a potentially dangerous situation. Further, if an injury or burglary occurs while no outdoor lights are on, the homeowner could be open to possible personal liability for negligence.
One solution to this problem of having to be home to turn on the light is to install a photocell activated switch such as the Model DEC-6308 from Leviton Corp. This switch will turn on an outdoor spot light whenever ambient light falls below a threshold level. One disadvantage with this switch is that the light will stay on all night until ambient light rises above the threshold level. While having the light on all night may be appropriate for some locations, it is not ideal for all lighting applications. For example, in the interest of energy conservation and minimizing electrical energy bills, most homeowners will opt to not have their lights on all night. Another problem with this solution is that a special fixture must be mounted somewhere outside and AC power must be wired to the outdoor fixture. This usually will require the services of a trained electrician at considerable expense to the property owner.
Another possible solution for providing control of an outdoor light is to buy an in-wall timer switch such as the Model EL483 from Intermatic Corp. These switches are reasonably priced, relatively easy to install and can turn outside lights on and off at preprogrammed times. While this solution overcomes some disadvantages of prior switches, it has significant shortcomings. For example, since dusk changes between four and five hours over the course of a year, either the lights will be on during daylight hours (a sure indication to a potential burglar that no one is at home) or the timer will have to be regularly reprogrammed to keep up with the changing time of sunset. Therefore, the homeowner is burdened with a task of regularly reprogramming the timer. Moreover, the current timer switches of this type are somewhat intimidating to operate for “technophobes”, children, and the elderly.
A further outdoor lighting solution includes an outdoor light which has a photosensor and a pre-set timer which functions to turn the light on at dusk or dark and then off at a pre-set number of hours after the light turns on. An operator sets the pre-set number of hours of how long the light should remain on after dusk/dark. For example, if the timer is set for five hours, the light will come on at dusk/dark, whenever that occurs, and then the timer will turn the light off five hours later. A disadvantage with this type of lighting option is that depending on when sunset is, if the pre-set time is too short, the lights may not remain on for a sufficient time into the night to meet ones security and safety needs. Alternative, setting the timer longer will mean that the lights will stay on longer than necessary during part of the year when sunset is later in the evening. Therefore, in order to maximize energy efficiency and home security, one is left with the option of having to periodically and repeatedly adjust the timer setting on the light.
In addition to using outdoor lights, homeowners often use indoor lights and lamps to provide home security and to ward off potential intruders. Devices to automatically turn on and off in-house lights and lamps include readily available separate timers and photosensors. Depending on the desired control, a consumer can use a timer to turn an electronic device, such as a lamp, on and off at specific times. Alternatively, using a photosensor switch, one can turn a lamp on and off when the outdoor light levels drop below a threshold level.
Typically, individual timer switches and photoelectric switches plug directly into a power outlet and the lamp or other electrical device plugs into the respective timer switch or photoelectric switch. In the case of a photoelectric sensor switch, the photoelectric sensor is placed in the proximity of a window or in a location which receives outdoor light so that the photoelectric sensor will operate properly to turn on and off the electric device at the appropriate lighting conditions. These in-house timer switches and photoelectric switches suffer from many of the same disadvantages as the switches for controlling outdoor lights which was previously noted.